Various network protocols have been used in communications among components of wireless communications systems to exchange information concerning authentication of users, routing of user data, quality of service (QoS), and charging for use of communications based on time, amount of data transferred, etc. For some time, the Remote Authentication Dial In User Service (RADIUS) protocol, adopted and promulgated by the Internet Engineering Task Force (IETF) of the Internet Society (ISOC) of Reston, Va. (becoming IETF 2000, RFC 2865, Remote Authentication Dial In User Service), was widely adopted and used. However, as both the complexity and bandwidth requirements of cellular communications have increased, various limitations of the RADIUS protocol have become more and more of an issue.
The Diameter protocol, also adopted and promulgated by IETF (becoming IETF 2003, RFC 3588, Diameter Base Protocol, and IETF 2003, RFC 4006 Diameter Credit-Control Application), was developed to replace the RADIUS protocol using many of the lessons learned from years of experience in using the RADIUS protocol. The Diameter protocol provides better security and a more flexible set of standardized messages, as well as incorporating better support for protocol extensions to better accommodate future developments. The Diameter protocol has, as its creators intended, begun to largely supplant the RADIUS protocol in communications between components of wireless communications systems.
Unfortunately, the increased flexibility of the Diameter protocol is accompanied by greater complexity in the formation, transmission and interpretation of the control messages that adhere to the Diameter protocol. As a result, use of the Diameter protocol may increase processing requirements and/or the volume of control messages exchanged between components of a wireless communications system.